batch size from $8$ lbs to $20$ lbs$.$ Calculate the THROUGHPUT RATE of each stage $($for a batch size of $20$ lb$)$ then answer the questions below, paying attention to the requested units. Where the answer is not a whole number, round to two decimal places.

a$)$ If Johnson were to increase the batch size to $20$ lbs$,$ which activity is the bottleneck? Please type the letter of your desired answer below.

a$)$ Batching

b$)$ Mixing

c$)$ Extruding

d$)$ Frying

e$)$ Cooling

f$)$ Customizing